Metals such as aluminum and their alloys have many uses in aerospace, commercial, and private industries. However, these metals have a propensity to corrode rapidly in the presence of water due to their low oxidation-reduction (redox) potential, thus significantly limiting the useful life of objects made from these metals, and/or increasing maintenance costs. These metals also may have a problem with paint adhesion, as the surface of the metal, when formed into an object, is generally very smooth.
The oxidation and degradation of metals used in aerospace and auto, commercial, and private industries is a serious and costly problem. To prevent or minimize the oxidation and degradation of metals, corrosion resistant coatings are applied to the metal's surface. Some coatings may also improve adhesion by using a sol-gel film between the metal and the upper layers of coating. Coatings providing corrosion resistance to metal substrates, while providing the necessary adhesion are therefore desired.